Milk contains a number of substances that have beneficial effects on blood pressure, including calcium, magnesium, potassium and bioactive whey proteins.
What is whey protein?
Whey proteins are found in the liquid part of milk that’s left over when casein proteins are solidified out to make cheese. These whey proteins represent around 20% of the protein found in whole cows’ milk and are a great source of easily-absorbed amino acids, some of which have powerful blood pressure lowering effects.
Whey proteins include beta-lactoglobulin, alpha-lactalbumin, lactoferrin, immunoglobulins, serum albumin, glycomacropeptide, various enzymes and numerous growth factors. Whey protein is particularly rich in the branched-chain amino acids, leucine, isoleucine and valine, which help to maintain muscle strength.
Whey concentrate is made by filtering whey to remove water and bring the percentage of whey proteins up to 70% to 80%. This concentrated whey solution is then spray dried to produce whey protein powder. Whey concentrate includes some milk fat and lactose sugar.
Whey isolate is made by removing all of the lactose and most of the milk fat from whey, to produce a high protein concentration of around 95%.
Whey hydrolysate is made by partially pre-digesting whey proteins to release short chains of amino acids called peptides. Hydrolysed whey proteins release their amino acids for absorptions more quickly after consumption.
Whey proteins act as ACE inhibitors
Peptides derived from several whey proteins have a powerful inhibitory effect against angiotensin-converting enzyme (ACE) and work in the same way as ACE-inhibitor drugs. Recent research also points to other antihypertensive mechanisms beyond ACE inhibition, through interactions with other hormones and dilation and elasticity of blood vessel walls. Antihypertensive peptides derived from lactoferrin, for example, can increase the activity of genes encoding proteins involved in nitric oxide (which dilates blood vessels) and prostaglandins (which regulate inflammation). Whey proteins have even been found to improve blood flow through coronary arteries.
Whey proteins effect on blood pressure
A study known as the Whey2Go trial asked 38 people to consume 28g whey protein twice a day, or 28 g casein protein twice a day, or a placebo, for 8 weeks. After a month’s break, each person switched to taking one of the other supplements so that eventually, all those tested took whey protein, and casein protein and placebo.
During each study period, ambulatory blood pressure measurements were taking for 24 hours. Significant reductions in average 24-hour blood pressure readings of 3.9/2.5 mmHg occurred in everyone when they were taking the whey-protein drinks compared with either casein or placebo. When taking whey protein supplements, the dilation of blood vessels was also significantly greater, total cholesterol levels were significantly lower, triglyceride levels decreased and their blood became less sticky.
Another study involved 33 obese, sedentary women (average age 30 years) with high blood pressure who were asked to follow an exercise program, and to take whey protein, or casein, or placebo for 4 weeks. Systolic blood pressure (upper reading) reduced by 5mmHg in those taking the protein supplements compared with those taking exercise alone (with placebo).
This may not seem like much, but the results from 32 studies involving over 197,000 people with hypertension, show that even small reductions on blood pressure are beneficial. For example, it is estimated that a 3 mmHg reduction in systolic blood pressure could reduce the risk of a fatal stroke by 8% and of a fatal heart attack by 5%.
Try taking why protein supplements
Whey protein drinks are increasingly popular, and if you have high blood pressure and are starting an exercise program to improve your fitness, you may gain double benefits from taking a whey protein product – improved muscle strength, and a more rapid improvement in your blood pressure readings.
There is sufficient evidence to support taking 28g whey protein supplements twice a day, for a month, to see how this approach benefits your blood pressure, as an individual.
Add whey protein powder to porridge, smoothies, or just make up according to instructions and have as a premeal drink – as a bonus you will eat less and likely lose weight, too. Some products are unflavoured, while others come in a range of flavours such as Double Rich Chocolate, Vanilla, Banana, Strawberry, White Chocolate Raspberry, Banana, Chocolate Mint or even Birthday Cake!
If your blood pressure is raised, self-monitoring is key to maintaining good control.
Click here for advice on choosing a blood pressure monitor to use at home.
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